Case report

Congenital sucrase-isomaltase deficiency presenting with failure to thrive, hypercalcemia, and nephrocalcinosis

John W Belmont^1,2 , Barbara Reid² , William Taylor⁵ , Susan S Baker⁶ , Warren H Moore⁴ , Michael C Morriss⁴ , Susan M Podrebarac² , Nancy Glass^2,3 and I David Schwartz⁵

¹Departments of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA 77030

²Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA 77030

³Department of Anesthesia, Baylor College of Medicine, Houston, TX, USA 77030

⁴Department of Radiology, Baylor College of Medicine, Houston, TX, USA 77030

⁵Department of Pediatrics, University of South Carolina School of Medicine, Columbia, SC, USA 29203

⁶Kaleida Health Children's Hospital Laboratory, Buffalo, NY, USA

author email corresponding author email

BMC Pediatrics 2002, 2:4doi:10.1186/1471-2431-2-4

Published:	25 April 2002

Abstract

Background

Disaccharide Intolerance Type I (Mendelian Interance in Man database: *222900) is a rare inborn error of metabolism resulting from mutation in sucrase-isomaltase (Enzyme Catalyzed 3.2.1.48). Usually, infants with SI deficiency come to attention because of chronic diarrhea and nutritional evidence of malabsorption.

Case Presentation

We describe an atypical presentation of this disorder in a 10-month-old infant. In addition to chronic diarrhea, the child displayed severe and chronic hypercalcemia, the evaluation of which was negative. An apparently coincidental right orbital hemangioma was detected. Following identification of the SI deficiency, an appropriately sucrose-restricted, but normal calcium diet regimen was instituted which led to cessation of diarrhea, substantial weight gain, and resolution of hypercalcemia.

Conclusions

This case illustrates that, similar to congenital lactase deficiency (Mendelian Interance in Man database: *223000, Alactasia, Hereditary Disaccharide Intolerance Type II), hypercalcemia may complicate neonatal Sucrase-Isomaltase deficiency. Hypercalcemia in the presence of chronic diarrhea should suggest disaccharide intolerance in young infants.